Question

The two ends of a metal rod are maintained at temperature ${100}^{o}C$ and ${110}^{o}C$. The rate of heat flow in the rod is found to be 4.0 J/s. If the ends are maintained at temperatures ${200}^{o}C$ and ${210}^{o}C$, the rate of heat flow will be

• A. 8.0 J/s
• B. 4.0 J/s
• C. 44.0 J/s
• D. 16.8 J/s

Answer 1

The correct option is B 4.0 J/s

Heat flow is given as
$\frac{\Delta Q}{\Delta t}=kA\frac{dT}{dx}$
as the temperature difference and length of rod are constant, the heat flow will be remain constant, it's value will be equal to 4 J, correct answer is option B.